Issue link: http://read.dmtmag.com/i/859318
Coolants Background & Properties castrol.com/GPS 800 255 4417 May 2025 GPS Important Properties: Coolant available that contains the SCA (pre-charged antifreeze) and the proper water to antifreeze ratio (pre- charged/pre-mixed). See Types of Antifreeze for more information. e SCA prevents the following types of wear and cooling system problems: rust, oxidation, corrosion of iron and steel components, pitted cylinder liners and water pump impellers. Pitting (also known as cavitation) is one of the most common side effects of using antifreeze without SCA. During pitting, the liner vibrates away from the coolant, creating an area of low pressure. is area causes the coolant to vaporize, leaving behind vapor bubbles that can implode at pressures of 60,000 psi. is implosion can remove a chunk of metal liner in as little as 50,000 miles. Radiator Water Pump Cylinder Block Thermostat Housing Cylinder Head Water Bypass Block Heater Oil Cooler Cylinder Liners Coolant affects an overwhelming number of engine and cooling components as shown in the illustration above. Problems resulting from leaks, over concentration or lack of SCA can affect these critical engine areas. To avoid coolant-related problems, use a pre-mixed, pre-charged antifreeze and check for proper treat rates twice a year. A test of the pH level, SCA level and freeze point can help determine the condition of antifreeze. Aluminum vs. Iron-Based Cooling Systems Cooling systems in cars and light trucks contain more aluminum parts—a much lighter weight metal—than iron components. ese aluminum parts require special protection from antifreeze by using performance- directed levels of silicates in the formulation. Heavy-duty gasoline and diesel engines are typically constructed with more cast-iron and have iron-based cooling systems. e iron in the cooling system of heavy-duty engines requires additional iron corrosion protection that antifreeze with higher silicate levels cannot provide. For this reason, an antifreeze that contains very low silicate levels and more iron protection is preferred. G4 ecastrof